USP Proposes Recombinant Endotoxin Test Option for Water Monographs

In Pharmacopeial Forum (PF) 52(1), January 2026, the U.S. Pharmacopeia (USP) proposed adding an alternative endotoxins method, <86> Bacterial Endotoxins Test Using Recombinant Reagents, alongside the traditional <85> Bacterial Endotoxins Test. If adopted, the change would impact several USP monographs, including Water for Injection, Sterile Water for Injection, Water for Hemodialysis, Pure Steam, and other sterile waters, while maintaining existing endotoxin limits.

Chapter <86>, which relies on animal-free recombinant reagents, is already an official USP method. The proposal would, for the first time, explicitly permit its use in USP water monographs. Implementation would require product-specific verification by users, including review of supplier validation data and internal suitability testing in line with <1226> Verification of Compendial Procedures. Regulators may also request comparative data against <85>.

The proposal is open for public comment. If approved, the revised monographs could become effective in 2027.

08-02-2026